Vehicles such as motorcycles which are equipped with keyless entry systems enabling users to lock or unlock doors or to start engines by button operations without inserting ignition keys into key cylinders have come into wide use. In each keyless entry system, a door lock control system and an engine control system are controlled by electric waves of a transmitter incorporated in the body of an ignition key. For example, this ignition key equipped with the transmitter is called a smart key.
There has been proposed a vehicle which is equipped with a keyless entry system and has a control device which enables a user to easily make the vehicle usable without using a smart key in an emergency, for example, in a case where the smart key is lost or broken (see Patent Document 1 for instance). This control device includes a display unit which flashes on the occasion of inputting a password number for authentication to permit use of the vehicle, and a password number input unit for inputting the password number according to the number of flashing times of the display unit, thereby simplifying password number input work of the user.
Patent Document 1: Japanese Patent Application Publication No. 2008-037182A
Recently, ships using keyless entry systems as described above have been developed. However, in circumstances, ships are different from vehicles such as motorcycles which are integrated with engines, in that outboard motors including engines are configured so as to be attachable to and detachable from the bodies of ships. Also, in case of some kinds of ships, a plurality of outboard motors is attached to the body of a ship. These special circumstances are required to be considered to design keyless entry systems for ships.